fs/nfs/nfs4_fs.h

   1 /*
   2  * linux/fs/nfs/nfs4_fs.h
   3  *
   4  * Copyright (C) 2005 Trond Myklebust
   5  *
   6  * NFSv4-specific filesystem definitions and declarations
   7  */
   8
   9 #ifndef __LINUX_FS_NFS_NFS4_FS_H
  10 #define __LINUX_FS_NFS_NFS4_FS_H
  11
  12 #if defined(CONFIG_NFS_V4_2)
  13 #define NFS4_MAX_MINOR_VERSION 2
  14 #elif defined(CONFIG_NFS_V4_1)
  15 #define NFS4_MAX_MINOR_VERSION 1
  16 #else
  17 #define NFS4_MAX_MINOR_VERSION 0
  18 #endif
  19
  20 #if IS_ENABLED(CONFIG_NFS_V4)
  21
  22 #define NFS4_MAX_LOOP_ON_RECOVER (10)
  23
  24 #include <linux/seqlock.h>
  25
  26 struct idmap;
  27
  28 enum nfs4_client_state {
  29         NFS4CLNT_MANAGER_RUNNING  = 0,
  30         NFS4CLNT_CHECK_LEASE,
  31         NFS4CLNT_LEASE_EXPIRED,
  32         NFS4CLNT_RECLAIM_REBOOT,
  33         NFS4CLNT_RECLAIM_NOGRACE,
  34         NFS4CLNT_DELEGRETURN,
  35         NFS4CLNT_SESSION_RESET,
  36         NFS4CLNT_LEASE_CONFIRM,
  37         NFS4CLNT_SERVER_SCOPE_MISMATCH,
  38         NFS4CLNT_PURGE_STATE,
  39         NFS4CLNT_BIND_CONN_TO_SESSION,
  40         NFS4CLNT_MOVED,
  41         NFS4CLNT_LEASE_MOVED,
  42         NFS4CLNT_DELEGATION_EXPIRED,
  43 };
  44
  45 #define NFS4_RENEW_TIMEOUT              0x01
  46 #define NFS4_RENEW_DELEGATION_CB        0x02
  47
  48 struct nfs_seqid_counter;
  49 struct nfs4_minor_version_ops {
  50         u32     minor_version;
  51         unsigned init_caps;
  52
  53         int     (*init_client)(struct nfs_client *);
  54         void    (*shutdown_client)(struct nfs_client *);
  55         bool    (*match_stateid)(const nfs4_stateid *,
  56                         const nfs4_stateid *);
  57         int     (*find_root_sec)(struct nfs_server *, struct nfs_fh *,
  58                         struct nfs_fsinfo *);
  59         void    (*free_lock_state)(struct nfs_server *,
  60                         struct nfs4_lock_state *);
  61         int     (*test_and_free_expired)(struct nfs_server *,
  62                         nfs4_stateid *, struct rpc_cred *);
  63         struct nfs_seqid *
  64                 (*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
  65         int     (*session_trunk)(struct rpc_clnt *, struct rpc_xprt *, void *);
  66         const struct rpc_call_ops *call_sync_ops;
  67         const struct nfs4_state_recovery_ops *reboot_recovery_ops;
  68         const struct nfs4_state_recovery_ops *nograce_recovery_ops;
  69         const struct nfs4_state_maintenance_ops *state_renewal_ops;
  70         const struct nfs4_mig_recovery_ops *mig_recovery_ops;
  71 };
  72
  73 #define NFS_SEQID_CONFIRMED 1
  74 struct nfs_seqid_counter {
  75         ktime_t create_time;
  76         int owner_id;
  77         int flags;
  78         u32 counter;
  79         spinlock_t lock;                /* Protects the list */
  80         struct list_head list;          /* Defines sequence of RPC calls */
  81         struct rpc_wait_queue   wait;   /* RPC call delay queue */
  82 };
  83
  84 struct nfs_seqid {
  85         struct nfs_seqid_counter *sequence;
  86         struct list_head list;
  87         struct rpc_task *task;
  88 };
  89
  90 static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
  91 {
  92         if (seqid_mutating_err(-status))
  93                 seqid->flags |= NFS_SEQID_CONFIRMED;
  94 }
  95
  96 /*
  97  * NFS4 state_owners and lock_owners are simply labels for ordered
  98  * sequences of RPC calls. Their sole purpose is to provide once-only
  99  * semantics by allowing the server to identify replayed requests.
 100  */
 101 struct nfs4_state_owner {
 102         struct nfs_server    *so_server;
 103         struct list_head     so_lru;
 104         unsigned long        so_expires;
 105         struct rb_node       so_server_node;
 106
 107         struct rpc_cred      *so_cred;   /* Associated cred */
 108
 109         spinlock_t           so_lock;
 110         atomic_t             so_count;
 111         unsigned long        so_flags;
 112         struct list_head     so_states;
 113         struct nfs_seqid_counter so_seqid;
 114         seqcount_t           so_reclaim_seqcount;
 115         struct mutex         so_delegreturn_mutex;
 116 };
 117
 118 enum {
 119         NFS_OWNER_RECLAIM_REBOOT,
 120         NFS_OWNER_RECLAIM_NOGRACE
 121 };
 122
 123 #define NFS_LOCK_NEW            0
 124 #define NFS_LOCK_RECLAIM        1
 125 #define NFS_LOCK_EXPIRED        2
 126
 127 /*
 128  * struct nfs4_state maintains the client-side state for a given
 129  * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
 130  *
 131  * OPEN:
 132  * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
 133  * we need to know how many files are open for reading or writing on a
 134  * given inode. This information too is stored here.
 135  *
 136  * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
 137  */
 138
 139 struct nfs4_lock_state {
 140         struct list_head        ls_locks;       /* Other lock stateids */
 141         struct nfs4_state *     ls_state;       /* Pointer to open state */
 142 #define NFS_LOCK_INITIALIZED 0
 143 #define NFS_LOCK_LOST        1
 144         unsigned long           ls_flags;
 145         struct nfs_seqid_counter        ls_seqid;
 146         nfs4_stateid            ls_stateid;
 147         atomic_t                ls_count;
 148         fl_owner_t              ls_owner;
 149 };
 150
 151 /* bits for nfs4_state->flags */
 152 enum {
 153         LK_STATE_IN_USE,
 154         NFS_DELEGATED_STATE,            /* Current stateid is delegation */
 155         NFS_OPEN_STATE,                 /* OPEN stateid is set */
 156         NFS_O_RDONLY_STATE,             /* OPEN stateid has read-only state */
 157         NFS_O_WRONLY_STATE,             /* OPEN stateid has write-only state */
 158         NFS_O_RDWR_STATE,               /* OPEN stateid has read/write state */
 159         NFS_STATE_RECLAIM_REBOOT,       /* OPEN stateid server rebooted */
 160         NFS_STATE_RECLAIM_NOGRACE,      /* OPEN stateid needs to recover state */
 161         NFS_STATE_POSIX_LOCKS,          /* Posix locks are supported */
 162         NFS_STATE_RECOVERY_FAILED,      /* OPEN stateid state recovery failed */
 163         NFS_STATE_MAY_NOTIFY_LOCK,      /* server may CB_NOTIFY_LOCK */
 164 };
 165
 166 struct nfs4_state {
 167         struct list_head open_states;   /* List of states for the same state_owner */
 168         struct list_head inode_states;  /* List of states for the same inode */
 169         struct list_head lock_states;   /* List of subservient lock stateids */
 170
 171         struct nfs4_state_owner *owner; /* Pointer to the open owner */
 172         struct inode *inode;            /* Pointer to the inode */
 173
 174         unsigned long flags;            /* Do we hold any locks? */
 175         spinlock_t state_lock;          /* Protects the lock_states list */
 176
 177         seqlock_t seqlock;              /* Protects the stateid/open_stateid */
 178         nfs4_stateid stateid;           /* Current stateid: may be delegation */
 179         nfs4_stateid open_stateid;      /* OPEN stateid */
 180
 181         /* The following 3 fields are protected by owner->so_lock */
 182         unsigned int n_rdonly;          /* Number of read-only references */
 183         unsigned int n_wronly;          /* Number of write-only references */
 184         unsigned int n_rdwr;            /* Number of read/write references */
 185         fmode_t state;                  /* State on the server (R,W, or RW) */
 186         atomic_t count;
 187 };
 188
 189
 190 struct nfs4_exception {
 191         struct nfs4_state *state;
 192         struct inode *inode;
 193         nfs4_stateid *stateid;
 194         long timeout;
 195         unsigned char delay : 1,
 196                       recovering : 1,
 197                       retry : 1;
 198 };
 199
 200 struct nfs4_state_recovery_ops {
 201         int owner_flag_bit;
 202         int state_flag_bit;
 203         int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
 204         int (*recover_lock)(struct nfs4_state *, struct file_lock *);
 205         int (*establish_clid)(struct nfs_client *, struct rpc_cred *);
 206         int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
 207         int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
 208                 struct rpc_cred *);
 209 };
 210
 211 struct nfs4_add_xprt_data {
 212         struct nfs_client       *clp;
 213         struct rpc_cred         *cred;
 214 };
 215
 216 struct nfs4_state_maintenance_ops {
 217         int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
 218         struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
 219         int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
 220 };
 221
 222 struct nfs4_mig_recovery_ops {
 223         int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
 224                 struct page *, struct rpc_cred *);
 225         int (*fsid_present)(struct inode *, struct rpc_cred *);
 226 };
 227
 228 extern const struct dentry_operations nfs4_dentry_operations;
 229
 230 /* dir.c */
 231 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
 232                     unsigned, umode_t, int *);
 233
 234 /* super.c */
 235 extern struct file_system_type nfs4_fs_type;
 236
 237 /* nfs4namespace.c */
 238 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
 239                                          const struct qstr *);
 240 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 241                                struct nfs_fh *, struct nfs_fattr *);
 242 int nfs4_replace_transport(struct nfs_server *server,
 243                                 const struct nfs4_fs_locations *locations);
 244
 245 /* nfs4proc.c */
 246 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
 247 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
 248                           struct rpc_message *, struct nfs4_sequence_args *,
 249                           struct nfs4_sequence_res *, int);
 250 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int);
 251 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
 252 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
 253 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
 254 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
 255 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
 256 extern int nfs4_destroy_clientid(struct nfs_client *clp);
 257 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 258 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 259 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
 260 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 261 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 262                                   struct nfs4_fs_locations *, struct page *);
 263 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
 264                 struct page *page, struct rpc_cred *);
 265 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
 266 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, const struct qstr *,
 267                             struct nfs_fh *, struct nfs_fattr *);
 268 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 269 extern const struct xattr_handler *nfs4_xattr_handlers[];
 270 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
 271                 const struct nfs_open_context *ctx,
 272                 const struct nfs_lock_context *l_ctx,
 273                 fmode_t fmode);
 274
 275 #if defined(CONFIG_NFS_V4_1)
 276 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 277 {
 278         return server->nfs_client->cl_session;
 279 }
 280
 281 extern int nfs41_setup_sequence(struct nfs4_session *session,
 282                 struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
 283                 struct rpc_task *task);
 284 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
 285 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
 286 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
 287 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
 288                 struct nfs_fsinfo *fsinfo);
 289 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
 290                                   bool sync);
 291 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
 292                 struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
 293
 294 static inline bool
 295 is_ds_only_client(struct nfs_client *clp)
 296 {
 297         return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
 298                 EXCHGID4_FLAG_USE_PNFS_DS;
 299 }
 300
 301 static inline bool
 302 is_ds_client(struct nfs_client *clp)
 303 {
 304         return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
 305 }
 306
 307 static inline bool
 308 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 309                     struct rpc_clnt **clntp, struct rpc_message *msg)
 310 {
 311         struct rpc_cred *newcred = NULL;
 312         rpc_authflavor_t flavor;
 313
 314         if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
 315                 spin_lock(&clp->cl_lock);
 316                 if (clp->cl_machine_cred != NULL)
 317                         /* don't call get_rpccred on the machine cred -
 318                          * a reference will be held for life of clp */
 319                         newcred = clp->cl_machine_cred;
 320                 spin_unlock(&clp->cl_lock);
 321                 msg->rpc_cred = newcred;
 322
 323                 flavor = clp->cl_rpcclient->cl_auth->au_flavor;
 324                 WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
 325                              flavor != RPC_AUTH_GSS_KRB5P);
 326                 *clntp = clp->cl_rpcclient;
 327
 328                 return true;
 329         }
 330         return false;
 331 }
 332
 333 /*
 334  * Function responsible for determining if an rpc_message should use the
 335  * machine cred under SP4_MACH_CRED and if so switching the credential and
 336  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
 337  * Should be called before rpc_call_sync/rpc_call_async.
 338  */
 339 static inline void
 340 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 341                    struct rpc_clnt **clntp, struct rpc_message *msg)
 342 {
 343         _nfs4_state_protect(clp, sp4_mode, clntp, msg);
 344 }
 345
 346 /*
 347  * Special wrapper to nfs4_state_protect for write.
 348  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
 349  * that use machine cred use NFS_FILE_SYNC.
 350  */
 351 static inline void
 352 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 353                          struct rpc_message *msg, struct nfs_pgio_header *hdr)
 354 {
 355         if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
 356             !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
 357                 hdr->args.stable = NFS_FILE_SYNC;
 358 }
 359 #else /* CONFIG_NFS_v4_1 */
 360 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 361 {
 362         return NULL;
 363 }
 364
 365 static inline bool
 366 is_ds_only_client(struct nfs_client *clp)
 367 {
 368         return false;
 369 }
 370
 371 static inline bool
 372 is_ds_client(struct nfs_client *clp)
 373 {
 374         return false;
 375 }
 376
 377 static inline void
 378 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
 379                    struct rpc_clnt **clntp, struct rpc_message *msg)
 380 {
 381 }
 382
 383 static inline void
 384 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 385                          struct rpc_message *msg, struct nfs_pgio_header *hdr)
 386 {
 387 }
 388 #endif /* CONFIG_NFS_V4_1 */
 389
 390 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
 391
 392 extern const u32 nfs4_fattr_bitmap[3];
 393 extern const u32 nfs4_statfs_bitmap[3];
 394 extern const u32 nfs4_pathconf_bitmap[3];
 395 extern const u32 nfs4_fsinfo_bitmap[3];
 396 extern const u32 nfs4_fs_locations_bitmap[3];
 397
 398 void nfs40_shutdown_client(struct nfs_client *);
 399 void nfs41_shutdown_client(struct nfs_client *);
 400 int nfs40_init_client(struct nfs_client *);
 401 int nfs41_init_client(struct nfs_client *);
 402 void nfs4_free_client(struct nfs_client *);
 403
 404 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
 405
 406 /* nfs4renewd.c */
 407 extern void nfs4_schedule_state_renewal(struct nfs_client *);
 408 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
 409 extern void nfs4_kill_renewd(struct nfs_client *);
 410 extern void nfs4_renew_state(struct work_struct *);
 411 extern void nfs4_set_lease_period(struct nfs_client *clp,
 412                 unsigned long lease,
 413                 unsigned long lastrenewed);
 414
 415
 416 /* nfs4state.c */
 417 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
 418 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
 419 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
 420 int nfs4_discover_server_trunking(struct nfs_client *clp,
 421                         struct nfs_client **);
 422 int nfs40_discover_server_trunking(struct nfs_client *clp,
 423                         struct nfs_client **, struct rpc_cred *);
 424 #if defined(CONFIG_NFS_V4_1)
 425 int nfs41_discover_server_trunking(struct nfs_client *clp,
 426                         struct nfs_client **, struct rpc_cred *);
 427 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
 428 extern void nfs41_notify_server(struct nfs_client *);
 429 #else
 430 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
 431 {
 432 }
 433 #endif /* CONFIG_NFS_V4_1 */
 434
 435 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
 436 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
 437 extern void nfs4_purge_state_owners(struct nfs_server *);
 438 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
 439 extern void nfs4_put_open_state(struct nfs4_state *);
 440 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
 441 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
 442 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
 443 extern void nfs_inode_find_state_and_recover(struct inode *inode,
 444                 const nfs4_stateid *stateid);
 445 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
 446 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
 447 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
 448 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
 449 extern void nfs4_schedule_state_manager(struct nfs_client *);
 450 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 451 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
 452 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
 453 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
 454 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
 455 extern void nfs41_handle_server_scope(struct nfs_client *,
 456                                       struct nfs41_server_scope **);
 457 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
 458 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
 459 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
 460                 const struct nfs_lock_context *, nfs4_stateid *,
 461                 struct rpc_cred **);
 462
 463 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
 464 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
 465 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
 466 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
 467 extern void nfs_release_seqid(struct nfs_seqid *seqid);
 468 extern void nfs_free_seqid(struct nfs_seqid *seqid);
 469 extern int nfs40_setup_sequence(struct nfs4_slot_table *tbl,
 470                                 struct nfs4_sequence_args *args,
 471                                 struct nfs4_sequence_res *res,
 472                                 struct rpc_task *task);
 473 extern int nfs4_sequence_done(struct rpc_task *task,
 474                               struct nfs4_sequence_res *res);
 475
 476 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
 477
 478 extern const nfs4_stateid zero_stateid;
 479
 480 /* nfs4super.c */
 481 struct nfs_mount_info;
 482 extern struct nfs_subversion nfs_v4;
 483 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 484 extern bool nfs4_disable_idmapping;
 485 extern unsigned short max_session_slots;
 486 extern unsigned short max_session_cb_slots;
 487 extern unsigned short send_implementation_id;
 488 extern bool recover_lost_locks;
 489
 490 #define NFS4_CLIENT_ID_UNIQ_LEN         (64)
 491 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
 492
 493 /* nfs4sysctl.c */
 494 #ifdef CONFIG_SYSCTL
 495 int nfs4_register_sysctl(void);
 496 void nfs4_unregister_sysctl(void);
 497 #else
 498 static inline int nfs4_register_sysctl(void)
 499 {
 500         return 0;
 501 }
 502
 503 static inline void nfs4_unregister_sysctl(void)
 504 {
 505 }
 506 #endif
 507
 508 /* nfs4xdr.c */
 509 extern struct rpc_procinfo nfs4_procedures[];
 510
 511 struct nfs4_mount_data;
 512
 513 /* callback_xdr.c */
 514 extern struct svc_version nfs4_callback_version1;
 515 extern struct svc_version nfs4_callback_version4;
 516
 517 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
 518 {
 519         memcpy(dst->data, src->data, sizeof(dst->data));
 520         dst->type = src->type;
 521 }
 522
 523 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
 524 {
 525         if (dst->type != src->type)
 526                 return false;
 527         return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
 528 }
 529
 530 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
 531 {
 532         return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
 533 }
 534
 535 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
 536 {
 537         return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
 538 }
 539
 540 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
 541 {
 542         return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
 543 }
 544
 545 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
 546                 const nfs4_stateid *stateid)
 547 {
 548         return test_bit(NFS_OPEN_STATE, &state->flags) &&
 549                 nfs4_stateid_match_other(&state->open_stateid, stateid);
 550 }
 551
 552 #else
 553
 554 #define nfs4_close_state(a, b) do { } while (0)
 555 #define nfs4_close_sync(a, b) do { } while (0)
 556 #define nfs4_state_protect(a, b, c, d) do { } while (0)
 557 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
 558
 559 #endif /* CONFIG_NFS_V4 */
 560 #endif /* __LINUX_FS_NFS_NFS4_FS.H */